What is the management approach for a patient with a history of encephalitis, recently discharged for COVID-19 (Coronavirus Disease 2019), now presenting with morning nausea, vomiting, and worsening confusion?

Management of Post-COVID Encephalitis Patient with Morning Nausea, Vomiting, and Worsening Confusion

This patient requires immediate hospital admission for urgent neuroimaging (brain MRI), lumbar puncture, and close monitoring given the high-risk combination of prior encephalitis, recent COVID-19, and new neurological deterioration with morning symptoms suggesting increased intracranial pressure. 1, 2

Immediate Diagnostic Workup

Neurological Assessment Priority

• Obtain urgent brain MRI to evaluate for recurrent encephalitis, cerebral edema, or new inflammatory changes, as MRI showed abnormalities in 7.8% of COVID-19 encephalitis cases and is more sensitive than CT for detecting white matter hyperintensities (44.68% of cases) and temporal lobe involvement (17.02%) 3, 4
• Perform lumbar puncture to assess for pleocytosis and hyperproteinorachia, which are diagnostic hallmarks of COVID-19-associated encephalitis, though SARS-CoV-2 PCR in CSF is positive in only rare cases 5, 4
• Order EEG immediately, as this is the most sensitive test with abnormalities detected in 61.9% of COVID-19 encephalopathy/encephalitis cases 4

Laboratory Evaluation

• Complete blood count, comprehensive metabolic panel including liver enzymes, and serum inflammatory markers (CRP, ferritin, D-dimer) as these are frequently deranged in COVID-19-associated encephalitis 2, 6
• Repeat COVID-19 testing (PCR or antigen) to assess for reinfection or persistent infection 5
• CSF meningitis-encephalitis PCR panel to exclude other viral or bacterial causes of encephalitis 5

Critical Clinical Context

Timing and Risk Factors

• The average time from COVID-19 diagnosis to encephalitis onset is 14.5 days (range 10.8-18.2 days), but this patient is 3 months post-discharge, suggesting either delayed complication or new pathology 6
• Encephalitis occurs in approximately 0.215% of COVID-19 patients with a mortality rate of 13.4%, making this a life-threatening complication requiring aggressive management 6
• Morning nausea and vomiting are red flags for increased intracranial pressure, particularly when combined with worsening confusion in a patient with prior encephalitis history 1

Differential Considerations

• Recurrent or persistent COVID-19-associated encephalitis (mean onset 8 days from infection, but can be delayed) 4
• Post-infectious autoimmune encephalitis
• Cerebral edema or mass effect
• Metabolic encephalopathy from liver dysfunction (given GI symptoms can indicate hepatic involvement in COVID-19) 7

Treatment Approach

Empiric Therapy While Awaiting Results

• Initiate IV methylprednisolone (most commonly used treatment in 36.11% of COVID-19 encephalitis cases) pending diagnostic confirmation 3
• Consider IV immunoglobulin (IVIG) as second-line therapy (used in 27.77% of cases), particularly if autoimmune etiology suspected 3, 8
• All patients treated with corticosteroid boluses or immunoglobulins in the Spanish registry progressed favorably 4

Supportive Management

• Anti-edematous therapy if imaging confirms cerebral edema 5
• Anticoagulation prophylaxis given COVID-19 thrombotic risk 5
• Serial neurological assessments to monitor for deterioration 1
• Gastroprotection given GI symptoms and steroid therapy 5

Monitoring Parameters

Serial Testing Requirements

• Serial liver function tests given the association between elevated liver enzymes and severe disease in COVID-19 patients with GI symptoms 1
• Daily neurological examinations to assess mental status, focal deficits (ataxic gait was noted in one case), and signs of increased intracranial pressure 5
• Repeat imaging if clinical deterioration occurs 3

Common Pitfalls to Avoid

• Do not attribute confusion solely to metabolic causes without excluding structural or inflammatory CNS pathology in a patient with prior encephalitis 3, 6
• Do not delay lumbar puncture if no contraindications exist, as CSF analysis is critical for diagnosis even though SARS-CoV-2 PCR is rarely positive 5, 4
• Do not discharge without complete workup given the 28.26% in-hospital mortality rate for COVID-19-associated encephalitis 3
• Recognize that normal chest imaging does not exclude COVID-19-related neurological complications, as one case had encephalitis without pneumonia 5

Admission Criteria Met

This patient meets multiple criteria for hospital admission: significantly elevated risk of severe neurological complication, need for serial monitoring, requirement for IV therapy, and potential for rapid deterioration given prior encephalitis history 1, 2